English | 简体中文 | 繁體中文 | Русский язык | Français | Español | Português | Deutsch | 日本語 | 한국어 | Italiano | بالعربية
A aplicação CRUD (criar, ler, atualizar e excluir) é a mais importante aplicação para criar qualquer projeto. Ela oferece ideias para desenvolver grandes projetos. No SpringMVC, podemos desenvolver uma aplicação CRUD simples.
在这里,我们使用 Aqui, usamos JdbcTemplate
criar uma tabela99Aqui, usamos o emp existente no banco de dados MySQL4tabela. Ela possui
、Adicionar dependências ao arquivo pom.xml.
.0.-- <!//https:/mvnrepository.com/artifact/spring-pom.xml --> jdbc <dependency>/<groupId>org.springframework <groupId>org.springframework-webmvc/<artifactId>jdbc <version>5.1.1.RELEASE</version> </dependency> .0.-- <!//https:/mvnrepository.com/webmvc/org.apache.tomcat-tomcat --> jdbc jasper/<groupId>org.springframework <groupId>org.apache.tomcat-<artifactId>tomcat/<artifactId>jdbc <version>9java<12</version> </dependency> .0.-- <!//https:/mvnrepository.com/alpha/alpha-jasper --> jdbc javax.servlet/<groupId>org.springframework api-<artifactId>servlet/<artifactId>jdbc <version>3api-.0-1</version> </dependency> .0.-- <!//https:/mvnrepository.com/alpha/jstl --> jdbc javax.servlet/<groupId>org.springframework <groupId>javax.servlet/<artifactId>jdbc <version>1.2</version> </dependency> .0.-- <!//https:/mvnrepository.com/<artifactId>jstl/<artifactId>jstl-<artifactId>mysql-mysql --> jdbc java/<groupId>org.springframework <groupId>mysql-<artifactId>mysql-connector/<artifactId>jdbc <version>8java<11</version> </dependency> .0.-- <!//https:/mvnrepository.com/artifact/spring-org.springframework --> jdbc <dependency>/<groupId>org.springframework <groupId>org.springframework-<artifactId>spring/<artifactId>jdbc <version>5.1.1.RELEASE</version> </dependency>
Aqui, a classe bean contém variáveis correspondentes aos campos existentes no banco de dados (e métodos setter e getter).
Emp.java
package com.w3codebox.beans; public class Emp { private int id; private String name; private float salary; private String designation; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public float getSalary() { return salary; } public void setSalary(float salary) { this.salary = salary; } public String getDesignation() { return designation; } public void setDesignation(String designation) { this.designation = designation; } }
EmpController.java
package com.w3codebox.controllers; import java.util.List; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.ModelAttribute; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import com.w3codebox.beans.Emp; import com.w3codebox.dao.EmpDao; @Controller public class EmpController { @Autowired EmpDao dao;//will inject dao from XML file /*It displays a form to input data, here "command" is a reserved request attribute *which is used to display object data into form */ @RequestMapping("/empform") public String showform(Model m){ m.addAttribute("command", new Emp()); return "empform"; } /*It saves object into database. The @ModelAttribute puts request data * into model object. You need to mention RequestMethod.POST method * because default request is GET*/ @RequestMapping(value="/save, method = RequestMethod.POST) public String save(@ModelAttribute("emp") Emp emp){ dao.save(emp); retornar "redirecionar:/viewemp";//will redirect to viewemp request mapping } /* It provides list of employees in model object */ @RequestMapping("/viewemp" public String viewemp(Model m){ List<Emp> list = dao.getEmployees(); m.addAttribute("list", list); return "viewemp"; } /* It displays object data into form for the given id. * The @PathVariable puts URL data into variable.*/ @RequestMapping(value="/editemp/{id}" public String edit(@PathVariable int id, Model m){ Emp emp = dao.getEmpById(id); m.addAttribute("command", emp); return "empeditform"; } /* It updates model object. */ @RequestMapping(value="/editsave, method = RequestMethod.POST) public String editsave(@ModelAttribute("emp") Emp emp){ dao.atualizar(emp); retornar "redirecionar:/viewemp"; } /* Elimina o registro para o id fornecido na URL e redireciona para /viewemp */ @RequestMapping(value="/excluiremp/{id}",método = RequestMethod.GET) public String excluir(@PathVariable int id){ dao.excluir(id); retornar "redirecionar:/viewemp"; } }
Vamos criar uma classe DAO para acessar os dados necessários no banco de dados.
EmpDao.java
package com.w3codebox.dao; import java.sql.ResultSet; import java.sql.SQLException; import java.util.List; import org.springframework.jdbc.core.BeanPropertyRowMapper; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.jdbc.core.RowMapper; import com.w3codebox.beans.Emp; public class EmpDao { JdbcTemplate template; public void definirTemplate(JdbcTemplate template) { this.template = template; } public int salvar(Emp p){ String sql="insert into Emp99(nome,salário,designação) valores('"+p.getNome()+"',"+p.getSalário()+",'"+p.getDesignation()+"')"; return template.update(sql); } public int update(Emp p){ String sql="update Emp99 definir nome='"+p.getNome()+", salário="+p.getSalário()+"designação='"+p.getDesignation()+"' where id="+p.getId()+""; return template.update(sql); } public int delete(int id){ String sql="delete from Emp99 where id="+id+""; return template.update(sql); } public Emp getEmpById(int id){ String sql="select * from Emp99 where id=?"; return template.queryForObject(sql, new Object[]{id},new BeanPropertyRowMapper<Emp>(Emp.class)); } public List<Emp> getEmployees(){ return template.query("select * from Emp99",new RowMapper<Emp>(){ public Emp mapRow(ResultSet rs, int row) throws SQLException { Emp e=new Emp(); e.setId(rs.getInt(1)); e.setName(rs.getString(2)); e.setSalary(rs.getfloat(3)); e.setDesignation(rs.getString(4)); return e; } }); } }
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0"> <display-name>SpringMVC</display-name> <servlet <servlet-name>spring</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>spring</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app>
spring-servlet.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd"> <context:component-scan base-package="com.w3codebox.controllers></context:component-scan> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/></property> <property name="suffix" value=".jsp"></property> </bean> <bean id="ds" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver"></property> <property name="url" value="jdbc:mysql:<//localhost:3306/test"></property> <property name="username" value=""></property> <property name="password" value=""></property> </bean> <bean id="jt" class="org.springframework.jdbc.core.JdbcTemplate"> <property name="dataSource" ref="ds"></property> </bean> <bean id="dao" class="com.w3codebox.dao.EmpDao"> <property name="template" ref="jt"></property> </bean> </beans>
index.jsp
<a href="empform">Adicionar Funcionário</a> <a href="viewemp">Ver Funcionários</a>
empform.jsp
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form"%> <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> <h1>Adicionar novo Funcionário</h1> <form:form method="post" action="save"> <table > <tr> Nome : </td> <td><form:input path="name" /></td> </tr> <tr> Salário :</td> <td><form:input path="salary" /></td> </tr> <tr> Designação :</td> <td><form:input path="designation" /></td> </tr> <tr> td> </td> <td><input type="submit" value="Salvar" /></td> </tr> </table> </form:form>
empeditform.jsp
aqui"/SpringMVCCRUDSimple" é o nome do projeto. Se você usar outro nome de projeto, altere este nome. Para aplicações em tempo real, você pode fornecer o URL completo.
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form"%> <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> <h1>Editar Funcionário</h1> <form:form method="POST" action="/SpringMVCCRUDSimple/editsave"> <table > <tr> <td></td> <td><form:hidden path="id" /></td> </tr> <tr> Nome : </td> <td><form:input path="name" /></td> </tr> <tr> Salário :</td> <td><form:input path="salary" /></td> </tr> <tr> Designação :</td> <td><form:input path="designation" /></td> </tr> <tr> td> </td> <td><input type="submit" value="Editar Salvar" /></td> </tr> </table> </form:form>
viewemp.jsp
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form"%> <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%> <h1>Lista de Funcionários</h1> <table border="2" width="70%" cellpadding="2"> <tr><th>Id</th><th>Nome</th><th>Salário</th><th>Designação</th><th>Editar</th><th>Excluir</th></tr> <c:forEach var="emp" items="${list}"> <tr> ${emp.id}</td> ${emp.name}</td> ${emp.salary}</td> ${emp.designation}</td> <td><a href="editemp/${emp.id}>Editar</a></td> <td><a href="deleteemp/${emp.id}>Excluir</a></td> </tr> </c:forEach> </table> <br/> <a href="empform">Adicionar novo Funcionário</a>/a>
Saída:
Clique Adicionar Funcionáriovocê verá a seguinte tabela.
Preencha o formulário e então Clique em Salvarpara adicionar o item ao banco de dados.
Agora, clique EditarPara fazer algumas alterações nos dados fornecidos.
Agora, clique Editar e Salvarpara adicionar o item alterado ao banco de dados.
Agora, clique ExcluirExclua o item do banco de dados.